Strip forming apparatus



Oct. 5, 1948. c. w. HAZELETT 2,450,428

' STRIP FORMING APPARATUS Filed March 23, 1944 3 Sheets-Sheet l ATTORNEY3 Sheets-Sheet 2 INVENTOR 64 4254/65 M #4251577 BY WM ATTORNEY Oct. 5,1948. c. w. HAZELETT STRIP FORMING APPARATUS Filed March 23, 1944 Oct.5, 1948. c. w. HAZELETT 2,450,423

STRIP FORMING APPARATUS Filed March 25, 1944 3 Sheets-Sheet 5 UPPER Zfl/EL 0F 54 77/ ATTORNEY Patented Oct. 5, 1948 UNITED STATES PATENTOFFICE srmr FORMING APPARATUS Clarence W. Hazelett, Greenwich, Conn.Application Marcli as, 1944, Serial No. 527,704 13 Claims. (Cl. 22-513)1 This invention relates to a metal working apparatus for the productionof metal strip directly from molten metal. In brief, the formation ofmetal strip directly from molten metal is usually accomplished by thepassage of molten metal be- 6 tween a cooperating pair of moving coolingsurfaces. These cooling surfaces may comprise a pair of rolls or ringsbetween the peripheries of which the metal passes. On the other hand,the

cooling surfaces may comprise a ring toward the 10 inner periphery ofwhich presses a roll or ring for forming metal strip therebetween. Stillfurther, the cooling surfaces may comprise an endless belt adapted forcooperation with a roll and with means being provided for backing up theendless belt where it cooperates with the roll. Since rings and rollsfunction alike in apparatus of the general class described, I shallhereinafter use the term roll" as inclusive of both rings and rolls; inother words, the term roll will be used here in its generic sense,thereby simplifying and shortening the specification. L

It has been found, especially when forming thin metal strip, that it isbest to feed the metal bethat I now believe to be true from thosestudies of my invention that I have made. However, I do not wish thepatent claims to be granted to me to be limited by the theories I shallset forth, since those theories may not be entirely correct or completeas laterdevelopments may prove. It will tween the cooling surfaces froma bath of ,metal excess cooling, thereby preventing the use ofnonworking strip forming apparatus such as set forth in my Patent No.2,383,310, issued August 21, 1945. Thus, where light pressures aremaintained be tween the cooling surfaces for the passage of metaltherebetween, the excess cooling of the metal at the ends of the bathwill separate the cooling surfaces, spilling the molten metal from thebath of metal, and stopping the mill. This condition prevents the use ofcooling surfaces maintained under the light pressures that are necessaryto fabricate an un-worked metal strip of the type in which-upper andlower chilled films are welded together, in effect, for the formation ofmetal strip. 1

At this-point, it may be well to indicate that the invention-to bedescribed hereinafter has actually been used-by me in the manufacture ofmetal strip, and has been found extremely successful. In describing myinvention, I shall, of

necessity, outline certain theories of operation also be well toconsider that the apparatus I shall outline hereinafter is merelyexemplary of preferred means whereby my invention may be utilized, andthat other arrangements of the apparatus may be successfully usedfollowing my teachings to the prior art.

Efforts have been made, as witnessed by prior art patents, to overcomethe difficulties inherent in the use of damming means for baths ofmetal. Thus, the flanges or end dams of the cooling means have beenheated, it being thought that by this method the excess cooling at theends of the bath of metal might be obviated. Similarly, attempts havebeen made to apply more heat at the ends of the bath whereby to yielduniform cooling of the metal passing between the cooling surfaces. Theseexpedients have not been entirely satisfactory.

In my application supra, I eliminate the bath of metal entirely, but asI have already indicated,

it is not always possible or desirable to form strip without a bath ofmetal. The problem I, have thus outlined, and which for ,many years has0 confronted the art, thus remains unsolved.

It is the object of my invention to contribute an apparatus in which abath of metal is contained by cooling surfaces for feeding between thecooling surfaces for the forming of metal strip, while eliminatingexcess cooling of the metal at the ends of the bath. It is a furtherobject of my invention to contribute an apparatus in which the-metalstrip can be cooled uniformly throughout its width, and under uniformpressures throughout its width. While the contribution of my inventionis particularly valuable in making possible the use of non-workingcooling surfaces of the class outlined, with but light pressuresyieldingly holding the cooling surfacesyin operative relation, myinvention is useful also with other types of processes and apparatus aswill be readily apparent to those skilled in the art.

Those skilled in the art will further appreciate, upon a review ofmyinvention, that I have solved the long standing problem relating to theutilization of a bath of metal, by eliminating the excess cooling at theends of the metal bath, now inherent in all strip forming millsutilizing a bath of metal.

Those skilled in the art will of course appreciate those skilled in theart will readily appreciate the manner in which the basic contributionof my invention should be employed.

One feature of my invention whereby the objects thereof are achieved,resides in the utilization of strip forming portions of the coolingsurfaces as containing surfaces for the bath of metal. A further featureof my invention resides in the utilization of the ends of the coolingsurfaces as containing surfaces for the bath of metal, the said endsfunctioning simultaneously as portions of the cooling surfaces actuallyforming the metal strip through the passage of metal therebetween fromthe bath of metal. As illustrative of the broad nature of my invention,I shall first describe its utilization in an apparatus in which theouter peripheral surfaces of a pair of rolls function as the coolingmembers. Thereafter, I shall describe the invention embodied in anapparatus in which the outer peripheral surface of a roll forms onecooling surface and cooperates with another cooling surface that is theinner peripheral surface of a ring. My invention shall then be describedas embodied in an apparatus in which one cooling surface is the outerperiphery of a roll while the other cooling surface is a continuouslymoving metal belt.

I have thus outlined generally my invention in order that mycontribution to the art may be better understood. However, additionalfeatures of my invention will be presented in the specification thatfollows, and it is intended that those additional features be includedin the protection afforded by the patent claims to be granted me.

Referring now to the drawings, Fig. l is a vertical schematic view of amill utilizing my invention. Fig. 2 is a section taken along lines 2-2of 8. 1. Fig. 3 is a schematic vertical section through the secondmodification of my invention hereinabove outlined. Fig. 4 is a sectiontaken along lines l4 of Fig. 3. Fig. 5 is a schematic vertical sectionthrough the third modification of my invention hereinabove outlined.Fig. 6 is a section taken along lines 6-6 of Fig. 5. Fig.

'7 is a vertical section through the bath of metal taken substantiallyinthe same vertical plane as Fig. 1 and substantially along lines 1-! ofFig. 2. Figs. 8, 9, and are vertical sections similar to Fig. 7 buttaken in planes displaced laterally from that of Fig. 7 toward one endof the bath of metal as indicated by lines 8-8, 9-9, and Ill-I ll ofFig. 2.

Referring now more particularly to the drawings, and especially Figs. 1and 2, the lower cooling member of my apparatus is in the form of a ringII. It is preferably rotated by a power roll II that is pressedyieldingly against the outer periphery of the ring I through theintermediary of the metal strip I2 formed on the said outer periphery.The ring I0 is backed up by a back up roller i3 located diametricallyopposite the power roll H and supported in a conventional manner.

A further back up roll I4 is utilized for the ring 4 l0, and this backup roll serves to support the rather novel margin members l5, whosesurfaces It form, in effect, part of the lower cooling surface, ascontinuations of the peripheral surface of the ring i0. Endwiseexpansion of the ring III will naturally tend to separate the marginmembers II, and for that reason the left margin member I! in Fig. 2, ismaintained yieldingly against the ring Ill through a pressure ring I!carried by roll l4. The pressure exerted by the ring I1 is controlledthrough threaded bolts l8 and springs l9 maintained in pressing relationtothe ring H by the said bolts l8,

The upper cooling member 01' my invention is designated by referencenumeral 20, and is in the form of a hollow roll backed up by the outerraces 2i of ball bearings 22 rotating about shafts 23. The shafts 23 aresupported by some suitable member such as the lever 24 pivoted at 25. Bydetermining the pressure to be exerted by the races 2| against thesurfaces 26 of the roller 20, the pressure of the roller 20 relativelyto the ring it may be determined. In accordance with the preferredoperation of my invention, this pressure will be extremely light, inorder that the metal strip shall be formed without appreciable pressure,thus avoiding folding, segregation, and other difficulties that need.not here be discussed, and which are inherent in mills using fixed orhigh pressure cooling surfaces. However, my invention to be hereinaftermore particularly described, is of course applicable to otherarrangements of apparatus as is apparent to those skilled in the art.

Metal is deposited on the lower cooling surfaces or ring Ill, through asuitable distributor 30 and its chute 3|. It is quite apparent that themetal willbe deposited to form a bath B as best illustrated in Fig. 1.The upper containing surface of this bath will of course be the upperroll 20 and the surfaces 35 of its inwardly tapering ends, as is clearlyapparent from an examination of Fig. 2. 'The lower containing surfacefor the bath of metal will of course be the peripheral surface of thering I0, andthe peripheral surfaces ii of margin members l5.

It may be well to consider at this point that the margin surfaces It mayconceivably be integral extensions of the peripheral surface of the ringl0, with the said' ring being formed integrally with marginmembers l5.It will now be noted also that the ends of the bath of metal B will becontained particularly by the margin surfaces It and by the surfaces 35of the roll 20. So long as the bath B is maintained sufllciently low sothat it does not. rise to the point where it can not be contained by thesurfaces I8 and 35, the said surfaces will be quite effective in holdingthe metal bath against spilling at its ends. It seems rather apparentnow that surfaces It and 35 act not only to contain the ends ofthe metalbath B, but they are part of the surfaces used to form the metal stripby the passage of metal therebetween from said bath.

Thus, in Figs. 1 and 7 the metal of the bath is shown in contact withthe surface L of the lower roll and the surface U of the upper roll. InFig. 8, taken in a plane in which the lower surface has tapered upwardlyrelatively to the upwardly tapered surface of the upper roll, th lengthof surface L has decreased materially and so has the surface U. Ofcourse, the amount of metal in the bath is also smaller.

In Figs. 9 and 10 the surfaces L and U have further decreased and thebath of metal has also decreased in volume. It can now be said that thelower roll so tapers relatively to the upper roll as to decreaseprogressively the amount of metal to be cooled at the ends of the bath.It can also be said that the application of cooling surfaces to the bathof metal decreases toward the ends of the bath. It is further importantto consider that no cooling surface is in contact with an end of thebath of metal, so that my bath of metal is contained at its ends withoutend dams.

In other words, the time of contact of the molten bath with the coolingsurfaces is thus progressively less towards the ends of the bath,resulting in progressively less coolin of the ends of bath of metal.Because the actual metal at the ends of the bath is progressivelysmaller also, the decrease in the cooling rate is partially compensatedfor, in order that the cooling rate in the entire bath remain fairlyuniform. I can how ever, actually effect less cooling at the ends of thebath, if I so desire, as distinguished from the prior art where thecooling rate at the ends of the bath is so great as to have adeleterious effect.

It is also important to note that because there is less metal availableat the ends of the bath of metal, the metal strip that is formed by thecooling-surfaces may have edges of decreasing thickness.

The apparatus thus far described will of course have the usual coolingapparatus a pipe 36 being utilized for cooling the upper cooling member20 while a pipe 31 supplies water for cooling the lower cooling memberand the strip metal I2, I believe it unnecessary to describe myinvention in further detail since the basic contribution thereof is nowrather apparent.

In Figs. 3 and 4, a modification of my invention is shown, in which theequivalent of the lower cooling member of the first modification is arin 40 that is rotated in any suitable way and is backed up by a roller4| and further rollers 42 and 43, the strip metal 44 formed being drawnoff as shown. The upper cooling member is designated by referencenumeral 45 .and is of the same character, substantially, as the coolingmember 20 of the first modification. As in the first modification, it isbacked up by the races 46 of a pair of ball bearings 41.

In sectional Figure 4, it is well noted that the relationship of theseveral parts of Fig. 3 is exactly the same as the same parts in Figs. 1and 2. Thus, the lower cooling ring 40 is fitted with margin members l5asimilar to the members l5 of the first modification. A pressure ring Ilaon roller 4| has also the same function asthe pressure ring ll of thefirst modification. The upper cooling member 45 is tapered as at 35a inthe same manner as the cooling roll 20 is tapered at 35 inthe firstmodification. It is the function of the surfaces [6a of the marginmembers l5a to contain with the surfaces 35a the ends of the bath ofmetal B shown in Fig. 3. In functional operation, the apparatus of Figs.3 and 4, is ex- 'actly the same as that of Figs, 1 and 2. It is ofcourse possible, to move the roll 45 to one side of the center line C ifa deeper bath of metal is required, all of which will be quite apparentto those skilled in the art.

In Figs. 5 and 6, I illustrate a further modification of my invention.There, the upper cooling member 50 is exactly the same as th'euppercooling member 45 of the second modification, and the cooling member 20of the first modification. This is most clearly apparent from anexamina--. tion 01' Fig. 6. The lower cooling member takes the form of ametal belt 5| running between rollers 52 and 53. The side edges of thebelt are controlled by a backing roller 64 that is formed with taperingends 55. It is the function of these ends 55 to so deform the belt 5ithat along the section 6-6 of Fig. 5 and thereabove, it will assume thatshape shown in Fig. 6. The shape so assumed by the belt is approximatelythe shape of the cooling member Ill taken together with surfaces IS inFig. 2, or the cooling member 40 taken together with cooling surfaces"5a in Fig. 4. The tapered margins of belt iii are designated byreference numeral l6b in order to clarify the relation of thismodification to the two earlier modifications, The belt 5i and marginslGb will of course cooperate with the cooling surfaces of the roller 20,comprising the tapering portions 35b, in exactly the same manner as thecooling surfaces of the first two modifications cooperate.

It will now be apparent that my invention is such that it may be readilyutilized in many different types of apparatus for contributing theresults set forth. Thus, as is quite clearly apparent from an inspectionof Figs. 2, 4 and 6, the cooling surfaces in each of the severalmodifications have substantially the same operation and contributesubstantially the same type of metal strip.

I now claim:

1. In a combination of the class described, a pair of cooling memberseach having a cooling surface of circular cross section, means mountinsaid cooling members for rotation about parallel horizontal axes wherebysaid surfaces approach one another along a horizontal line for thepassage of metal therebetween to form continuous metal strip, said metalmoving from a bath of metal contained by said surfaces, and the marginsof saidcooling surfaces tapering upwardly at said line of approach forcontaining the ends of said bath of metal, the taper of the margins onone of said surfaces being such relatively to the taper ofthe margins ofthe other surface as to decrease progressively the amount of metal to becooled at the ends of said bath of metal and the area of the coolingsurfaces applied to the ends of said bath of metal.

2. In a combination of the class described, a pair of rolls havingperipheral cooling surfaces, means mounting said rolls for rotation withtheir cooling surfaces positioned so as to form the upper and lowercontaining surfaces of a bath of metal, the metal passing from said bathof metal and between said cooling surfaces, the ends of the coolingsurface of the'lower of said pair of rolls tapering outwardly relativelyto the axis of rotation thereof, the ends of the cooling surface of theupper of said rolls tapering inwardly relatively to the axis of rotationthereof, whereby said end surfaces form end dams, in effect, of saidcooling surfaces for containing the ends of the bath of metal betweenthe cooling surfaces of said rolls,- and the ends of the lower roll sotapering relatively to the ends of the upper roll as to de creaseprogressively the amount of metal to be cooled at the ends of said bathand the area of the cooling surfaces applied to the ends of said ends ofsaid cooling members tapering upwardly and toward one another whileremaining out of contact so that the cooling surfaces thereof containthe side ends of the bath of metal through said upward tapering ratherthan by end dams, and with the edges of the side ends of the bath ofmetal and the strip out of contact with an end cooling or containingsurface, the said cooling surfaces including said upwardly tapering endsfunctioning as complementary opposed cooling surfaces for the opposedupper and lower surfaces of the metal strip passing therebetween fromsaid bath as well as the containing surfaces for said bath.

4. In a combination of the class described, a pair of continuous coolingsurfaces, means mounting said cooling surfaces for movement whereby saidsurfaces approach one another along a horizontal line for the passage ofmetal therebetween to form continuous metal strip, said metal movingfrom a bath of metal contained by said surfaces, the lower of saidsurfaces being upwardly inelined from the line of approach of saidsurfaces whereby to form the lower containing surface of said bath ofmetal, the ends of said surfaces being upwardly tapered relatively toone another from the line of approach of said surfaces while remainingout of contact whereby to contain the side ends of said bath of metalthroughsaid upward tapering rather than by end dams, and with thecorresponding ends of the bath of metalout of contact with an endcooling or containing surface, and the rate of taper of said coolingsurfaces being such as to decrease progressively the amount of metal tobe cooled at the side ends of said bath of metal and the area of thecooling surfaces applied to the ends of said bath of metal.

5. In a combination of the classdescribed, an upper cooling memberhaving a continuous cooling surface and a lower cooling member having acontinuous cooling surface, means mounting said cooling members formovement whereby said surfaces approach one another along a horizontalline for the passage of metal therebetween to form a continuous metalstrip, the ends of said surfaces being upwardly tapered from said lineof approach while remaining out of contact whereby to form thecontaining surfaces for a bath of metal to be fed between said surfacesand contained between said surfaces through said upward tapering ratherthan by end dams, and with the edges of the side cnds of the bath ofmetal and the strip out of contact with an end cooling or containingsurface, and the said upper and lower surfaces tapering upwardly at saidline of approach substantially as described for progressively decreasingthe amount of metal to be cooled at the side ends of said bath of metaland the areas of the cooling surfaces applied to the ends of said bathof metal.

6. In a combination of the class described, an upper cooling memberhaving a continuous cooling surface and a lower cooling member having acontinuous cooling surface, means mounting said members for movementwhereby said surfaces approach one another along a horizonal line forthe passage of metal therebetween to form a continuous metal strip, thelower of said surfaces being upwardly inclined from said line ofapproach whereby to form the lower containing surface of a bath of metalto be fed between said surfaces and contained between said surfaces, andthe ends of said upper and lower surfaces tapering upwardly from saidline of approach and toward one another while remaining out of contactwhereby to contain the side ends of said bath of metal therebetweenthrough said upward tapering rather than by end dams, and with the edgesof the side ends of the bath of metal and the strip out of contact withan end cooling or containing surface, said surfaces functioningtherefore simultaneously as cooling surfaces for the opposed surfaces ofthe metal strip passing therebetween from said bath as well ascontaining surfaces, the taper of the ends of said surfaces being suchrelatively to oneanother as to decrease progressively the amount ofmetal to be cooled at the side ends of said bath of metal and the areaof the cooling surfaces applied to the ends of said bath of metal.

'7. In a combination of the class described, a pair of cooling membershaving cooling surfaces, means mounting said cooling members formovement whereby said surfaces approach one another along a horizontalline for the passage of metal therebetween to form continuous metalstrip, said metal moving from a bath of metal contained by saidsurfaces, one of said surfaces being upwardly inclined from said line ofapproach whereby to form the lower containing surface of said bath ofmetal, and the ends of said surfaces tapering upwardly at said line ofapproach and relatively to one another while remaining out of contactwhereby to contain the side ends of said bath of metal through saidupward tapering rather than by end dams, and with the edges of the sideends of the bath of metal and the strip out of contact with an endcooling or containing surface, the taper of the ends of the lowersurface being such relatively to the taper of the ends of the othersurface as to decrease progressively the amount of metal to be cooled atthe side ends of said bath of metal and the area of the cooling surfacesapplied to the ends of said bath of metal.

8. In a combination of the class described, a pair of cooling memberseach having a cooling surface of circular cross section, means mountingsaid cooling members for rotation about parallel horizontal axes wherebysaid surfaces approach one another for the passage of metal therebetweento form continuous metal strip, said metal moving from a bath of metalcontained by said surfaces, one of said surfaces being below the othersurface at said line of approach whereby to form the lower containingsurface of said bath of metal, and the ends of said cooling surfacestapering upwardly and toward one another while remaining out of contactwhereby to contain the ends of said bath of metal through said upwardtapering rather than by end dams, and with the edges of the side ends ofthe bath of metal and the strip out of contact with an end cooling orcontaining surface, said tapering ends forming simultaneously the upperand lower cooling surfaces of the metal strip passing between saidcooling members from said bath.

9. In a combination of the class described, a pair of rolls havingperipheral cooling surfaces, means mounting said rolls for rotationabout par: allel horizontal axes offset vertically and horizontally fromone another and with the line of nearest approach of said peripheralsurfaces below the plane of the uppermost portion of the peripheralsurface of the lower roll whereby said peripheral surfaces form theupper and lower containing surfaces for a bath of metal, the metalPassing from said bath between said cooling surfaces to form continuousmetal strip, the ends of said rolls so tapering upwardly at their lineof 9 approach while remaining out of contact as to contain the bath ofmetal through said upward tapering rather than by end dams, and with theedges of the side ends of the bath of metal and the strip out of contactwith an end cooling or containing surface, the peripheral surfaces ofthe tapered ends of said rolls thus forming cooling surfaces for themetal strip formed by the passage of metal between said rolls from saidbath of metal and containing surfaces for said bath of metal.

10. In a combination of the class described, a pair of rolls havingcooling surfaces for forming metal strip fed between said rolls from abath of metal contained between the cooling surfaces of the rolls, meansmounting said rolls for rotation about parallel vertically andhorizontally offset horizontal axes with the cooling surfaces of therolls positioned so as to form the upper and lower containing surfacesof a bath of metal, the ends of the cooling surface of the lower of saidpair of rolls tapering outwardly relatively to the axis of rotationthereof and the ends of the cooling surface of the upper of said rollstapering inwardly relatively to the axis of rotation thereof, the rateof taper being such that said end surf-aces remain in spaced relationwhile forming end dams, in effect, of said cooling surfaces forcontaining the ends of the bath of metal between the cooling surfaces ofsaid rolls through said tapering rather than by end dams, and with theside ends of the bath of metal and the strip moving between said rollsout of contact with an end cooling or con taining surface.

11. -In a combination of the class described, an outer roll having aninner peripheral cool-ing surface, an inner roll having an outerperipheral cooling surface, means mounting said rolls for rotation aboutparallel horizontal axes and said inner roll within said outer roll, thecooling surfaces of said rolls being adapted for the passage of metaltherebetween at their line of nearest approach, said metal moving from abath of metal contained between said surfaces with the inner peripheralsurface of the outer roll forming the lower containing surface for saidbath of metal, the ends of said rolls so tapering upwardly at their lineof approach while remaining out of contact as to contain the bath ofmetal through said upward tapering rather than by end dams, and with theedges of the side ends of the bath of metal and the strip out of contactwith an end cooling or containing surface, the surfaces of the taperedends of said rolls thus forming cooling surfaces for the metal stripformed by the passage of metal between said rolls from said bath ofmetal and containing surfaces for said bath of metal.

12. In a combination of the class described, an outer roll having aninterior cooling surface, an inner roll having an outer peripheralcooling surface, means mounting said rolls for rotation about parallelhorizontal axes with the peripheral cooling surface of the inner rolladapted for spacing from the inner surface of the outer roll at theirline of nearest approach for the of metal therebetween to formcontinuous metal strip, said metal moving from a bath of metal containedby said surfaces, the cooling surface of said outer roll forming thelower containing surface for said bath of metal, the ends of said rollsso tapering upwardly at their line of approach while remaining out ofcontact as to contain the bath of metal through said upward taperingrather than by end dams, and with the edges of the side ends of the bathof metal and the strip out of contact with an end cooling or containingsurface, the surfaces of the tapered ends of said rolls thus formingcooling surfaces for the metal strip formed by the passage of metalbetween said rolls from said bath of metal and containing surfaces forsaid bath of metal, and the tapering of the ends of the lower coolingsurface being such relatively to the tapering of the ends of the innersurface so as to decrease progressively the amount of metal to be cooledat the ends of said bath of metal, and the area of the cooling surfacesapplied to the ends of said bath of metal.

13. In a combination of the class described, a cooling roll having aperipheral cooling surface, a continuous belt-like member having acooling surface adapted to approach the peripheral surface of saidcooling roll in a downwardly inclined path, means for rotating said rolland moving said belt-like member, said cooling surfaces being adaptedfor the passage of metal therebetween at their line of nearest approachto form continuous metal strip, said metal flowing from a 'bath of metalcontained between said roll and the cooling surface of said belt-likemember above said line of nearest approach, the ends of said rolltapering inwardly relatively to the axis of rotation thereof and theends of the surface of said beltlike member tapering upwardly at andabove said line of approach while remaining out of contact with saidroll, whereby to contain the ends of said bath of metal through saidupward tapering rather than by end dams, and with the edges of the sideends of the bath of metal and the strip out of contact with an endcooling or containing surface, said tapering ends forming simultaneouslythe upper and lower cooling surfaces of the metal strip passing betweensaid cooling members from said bath.

CLARENCE W. HAZELETT.

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